Flint was one of the most coveted and valuable materials of the Stone Age, used for the manufacture of cutting tools and weapons.
Not only that, in addition to its hardness and ability to break easily into flakes with sharp edges, it added that when it was hit against other rocks it produced sparks, therefore ideal for making fire.
Humans soon discovered these qualities and since the Paleolithic they organized their extraction from the subsoil through wells and tunnels, a mining activity that had its greatest development during the Neolithic (in fact, it has never stopped extracting, and today there are still some mines , like those of Miorcani in Romania).
Neolithic mines have been found in many places around the world, including Belgium, France, Egypt, Spain, Germany, and the United Kingdom. In the latter country, possibly one of the most spectacular is Grimes Graves, located in Norfolk.
At first glance it looks like a field of small explosive craters, like those on World War I battlefields. Nothing could be further from the truth. It is an archaeological site made up of 433 mining wells built in the Neolithic era to reach the coveted silex veins.
Researchers have determined that they were exploited between approximately 3000 and 1900 BC. The wells cover an area of 37 hectares and the largest reach more than 14 meters deep and 12 meters in diameter on the surface.
It is estimated that at Grimes Graves, up to 2,000 tons of limestone had to be extracted to create the largest pits, which would have required the work of around 20 people over five months.
The deposit consists of three layers or veins of flint, which were exploited successively while the wells were being dug, the last and deepest being the richest of all. In the extraction works they would have used wooden platforms and ladders.
It is believed that later Anglo-Saxon invaders who arrived in the early 5th century had some idea of what the wells were used for, as they were the ones who named it in honor of Odin. One of Odin's epithets was Grimnir (the hooded one), and hence Grim’s Graben (the hooded man's quarry ).
In modern times its function and purpose were not discovered until the archaeologist William Greenwell excavated one of the wells in 1870 (the same Greenwell who two decades later would find the famous and enigmatic Drums of Folkton).
In the 28 pits dug up to 2008, several hundred tools made from deer antlers that the miners used as pickaxes have been found. Probably the complement was wooden shovels, since remains of them have been found in other deposits. Once the vein was reached vertically, something that is really impressive using deer antlers, horizontal galleries were dug following it to extract as much as possible.
It is estimated that between 16,000 and 18,000 tons of flint were extracted at Grimes Graves, which would be used to produce some 3 million tools, axes and other artifacts. Much of that raw material would probably be used for trade, and would be carved in far-flung places.
Only one or two of the wells were exploited at the same time, opening new ones every one or two years and filling the previous ones with the earth and rocks from the last ones.
The site is currently open to the public, who can explore the archaeological site, and even descend into one of the shafts, the only one of its kind that can be visited in the UK.